Lips

I have always struggled with lips, so I practiced drawing them on their own. These were surprisingly fun to draw and I'm even thinking about to turning one of them into a painting. The one in the middle is my favorite. I really like the look of the softer shading. Although these are much better than lips I have drawn in the past they are no where near perfect. Feel free to leave any tips or suggestions.
Materials- HB #2 Pencil